US007282740B2
`
`a2) United States Patent
`US 7,282,740 B2
`(10) Patent No.:
`Chikugawaetal.
`(45) Date of Patent:
`Oct. 16, 2007
`
`
`(54) SEMICONDUCTOR LIGHT EMITTING
`DEVICE
`
`(75)
`
`Inventors: Hiroshi Chikugawa, Kashihara (JP);
`Yoshihiko Yamamoto, Yamatokoriyama
`hes
` }
`(JP); Eiji Kametani, Yamatotakada (JP)
`(73) Assignee: Sharp Kabushiki Kaisha, Osaka (JP)
`
`(*) Notice:
`
`Subject to any disclaimer, the term ofthis
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`6,355,946 BL*
`3/2002 Ishinaga oo... eee 257/98
`6,376,902 B1*
`... 257/678
`4/2002 Arndt
`......00..
`
`6,486,543 B1* 11/2002 Sano et al. we. 257/684
`
`
`6,603,148 BL*
`8/2003 Sano et al.
`ee 257/98
`2002/0190262 AL* 12/2002 Nitta et al. oe 257/99
`2003/0116769 Al
`6/2003 Songetal.
`2003/0168720 AL*
`9/2003 Kamada w.eccccsececeeceeee 257/666
`2004/0188719 Al*
`9/2004 Nawashiro et al.
`......... 257/200
`
`Jp
`JP
`JP
`
`FOREIGN PATENT DOCUMENTS
`9002-176203
`6/2002
`2003-15615
`4/2003
`2003 -197974
`7/2003
`
`(21) Appl. No.: 11/013,617
`(22) Filed:—Dee. 15, 2004 * cited by examiner
`
`
`,
`oo.
`Primary Examiner—Zandra V. Smith
`Prior Publication Data
`Assistant Examiner—Tsz Chiu
`US 2005/0133939 Al
`Jun. 23, 2005
`(74) Attorney, Agent, or Firm—Morrison & Foerster, LLP
`
`(65)
`
`Foreign Application Priority Data
`(30)
`Dec. 17, 2003
`(IP)
`aeecitsesecteeeteesees 2003-419585
`(51)
`Int. Cl.
`(2006.01)
`HOIL 27/15
`257/79: 257/13: 257/98:
`(52) US. Cl
`_ 957/99.257/103: 257/433: 357/434:257/704
`58)
`Field of Cl
`h
`,
`, 357/98
`fi
`ti
`S
`Field
`of
`Classi S57/79013. 99.103.433. 434. 70.4
`(58)
`lication
`file
`f
`°
`1 t ,
`oh hist
`,
`ee applicalon
`tle
`TOF complete search
`DIStory:
`References Cited
`U.S. PATENT DOCUMENTS
`
`(56)
`
`S
`
`ABSTRACT
`(57)
`A light emitting element is die-bonded to a portion of a lead
`frame exposed at the bottom of an opening formed at a top
`face of a resin package. A reflector to direct light emitted
`from the light emitting element towards a predetermined
`direction is attached to the top face of the resin package.
`Lead terminals are arranged so as to protrude from two
`opposite side regions ofthe resin package. A predetermined
`lead terminal among the plurality of lead terminals, con-
`nected to a portion where the light emitting element is
`die-bonded, is bent upwards, and solderedto the reflector by
`solder paste.
`
`5,660,461 A *
`
`8/1997 Ignatius et al.
`
`............ 362/241
`
`2 Claims, 8 Drawing Sheets
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`
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`Cree Ex. 1006
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`Page 1
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 1 of 8
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`US 7,282,740 B2
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`FIG.1
`FIG.2
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`Oct. 16, 2007
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`Sheet 2 of8
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`US 7,282,740 B2
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`U.S. Patent
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`FIG.3
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`FIG.4
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 3 of8
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`US 7,282,740 B2
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`FIG.5
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 4 of8
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`US 7,282,740 B2
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`FIG.6
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`FIG.7
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 5 of8
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`FIG.8
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`FIG.9
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`FIG.10
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 6 of8
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`US 7,282,740 B2
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`FIG.11
`FIG.12
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`4b
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`Oct. 16, 2007
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`Sheet 7 of8
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`US 7,282,740 B2
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`FIG.13
`FIG.14
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`4b
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`2
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`4b
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`2
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`U.S. Patent
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`Oct. 16, 2007
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`Sheet 8 of8
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`US 7,282,740 B2
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`FIG.15
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`PRIOR ART
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`US 7,282,740 B2
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`1
`SEMICONDUCTOR LIGHT EMITTING
`DEVICE
`
`This nonprovisional application is based on Japanese
`Patent Application No. 2003-419585 filed with the Japan
`Patent Office on Dec. 17, 2003, the entire contents of which
`are hereby incorporated by reference.
`
`5
`
`BACKGROUND OF THE INVENTION
`
`1. Field of the Invention
`
`Thepresent invention relates to semiconductorlight emit-
`ting devices, and moreparticularly, to a semiconductor light
`emitting device including a light emitting element.
`2. Description of the Background Art
`In general semiconductorlight emitting devices employed
`as the illumination device of a camera, the backlight of a
`liquid crystal display device, and the like, much current is
`conducted to achieve higher luminosity. However, a large
`current flow to the semiconductorlight emitting device will
`cause increase of the temperature of the light emitting
`element per se, leading to poor light emitting efficiency to
`degrade the light emitting element in the worst case.
`Therefore, measures to release the heat generated at the
`light emitting element outside efficiently in order to lower
`the temperature of the light emitting element have been
`adopted. One such measure is to increase the area or the
`thickness of the lead frame to which the light emitting
`elementis die-bonded. Another known measureis to replace
`the material around the light emitting element with a mate-
`rial of high heat conductance.
`In order to achieve high luminosity in the semiconductor
`light emitting device,
`the method of directing the light
`emitted from a light emitting element to a specified direction
`is employed. A resin lens or a reflector is attached to direct
`light towards the specified direction.
`Additionally, a semiconductor light emitting device hav-
`ing the aforementioned measures combined is proposed to
`emit light of higher luminosity towardsa specified direction.
`By way of example, one such semiconductor light emitting
`device disclosed in Japanese Patent Laying-Open No. 2003-
`115615 will be described hereinafter. Referring to FIG. 15,
`a light emitting element 103 and a reflector 105 are provided
`on the surface of a substrate 101. Two leads 104a@ and 1044
`
`of light emitting element 103 is soldered 107 to the wiring
`of substrate 101. A predetermined resin 109 is provided at
`the region of leads 104a and 1044 andtheregion ofreflector
`105.
`
`In this semiconductor light emitting device, leads 104a
`and 1044 are brought into direct contact with resin 109 to
`achieve heat dissipation by allowing the heat generated at
`light emitting element 103 to be conductedto reflector 105
`via resin 109.
`
`Additionally, Japanese Patent Laying-Open Nos. 2002-
`176203 and 2003-197974 disclose a semiconductor light
`emitting device that achieves heat dissipation by conducting
`the heat generated at a light emitting elementto a reflector
`via resin having high heat conductivity. The semiconductor
`light emitting device disclosed in Japanese Patent Laying-
`Open No. 2002-176203 has the reflector formed integrally
`with the lead to allow direct conduction of heat generated at
`the light emitting elementto the reflector without the inter-
`vention of resin and thelike.
`
`The semiconductor light emitting devices set forth above
`had the following problems. If the heat generated atthe light
`emitting element is to be conducted to a reflector via resin,
`the resin must be cured with the reflector fixed at a prede-
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`termined location with respect to the substrate and the light
`emitting element so as to achieve fixation between the
`reflector and the substrate. Therefore, a dedicated jig to
`position the reflector at predetermined site was required
`since heat conduction cannot be achieved efficiently if the
`position of the reflector is deviated. Furthermore,
`it was
`necessary to control the amount of resin during the fixation
`of the reflector so that the resin does not flow excessively to
`a region where resin is not required. In the case where the
`reflector and lead are formed integrally, the semiconductor
`light emitting device will have the reflector covered with
`mold resin since the reflector and lead are formedintegrally
`from the beginning. Thus, there was the problem that heat
`cannot be released efficiently to the air from the reflector.
`
`SUMMARY OF THE INVENTION
`
`In view of the foregoing, an object of the present inven-
`tion is to provide a semiconductor light emitting device that
`can achieve heat conduction reliably towards a reflector and
`that can release heat efficiently from the reflector to the air.
`A semiconductor light emitting device according to the
`present invention includes a lead frame, a semiconductor
`light emitting element, a sealing member, and a reflector.
`The lead frame includes a plurality of lead terminals. The
`semiconductor light emitting element is die-bonded to the
`lead frame. The sealing member seals the lead frame such
`that each ofthe plurality of lead terminals and the semicon-
`ductor light emitting element are exposed. The reflector is
`attached to the sealing member to emit the light output by
`the semiconductor light emitting element towards one direc-
`tion. A predetermined lead terminal amongthe plurality of
`lead terminals, connected to the region of the lead frame to
`which the semiconductor light emitting device is die-
`bonded, is arranged towards the side where the reflector is
`located to be connected to the reflector.
`In accordance with such a configuration, a predetermined
`lead terminal connected to the region where the semicon-
`ductor light emitting device is die-bonded is connected to
`the reflector. Accordingly, the heat generated at the semi-
`conductor light emitting elementis reliably conducted to the
`reflector via the predetermined lead terminal. As a result, the
`heat conductedto the reflector can be released efficiently by
`the reflector.
`
`In order to couple the reflector with the predetermined
`lead terminal by, for example, attachment,
`the reflector
`preferably includes an attach region to attach the predeter-
`mined lead terminal. Particularly,
`it is desirable that the
`predetermined lead terminal is fixed to the reflector by a
`conductive material.
`The sealing memberis formed having side regions facing
`each other. When the plurality of lead terminals are respec-
`tively arranged so as to protrude from the sealing member
`along one of the side regions facing each other, the prede-
`termined lead terminal is preferably arranged at one end of
`the plurality of lead terminals respectively disposed along
`one of the side regions.
`Accordingly, the predetermined lead terminal can be bent
`towardsthe region of the sealing member wherethe reflector
`is disposed without covering the semiconductor light emit-
`ting element exposed at the sealing member. The area of
`connection betweenthe reflector and the predetermined lead
`terminal can be ensuredto allow the reflector to be supported
`and fixed morestably.
`Furthermore, in the case where there is another predeter-
`mined lead terminal connected to the portion of the lead
`frame to which the semiconductor light emitting element is
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`US 7,282,740 B2
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`3
`is
`that another predetermined lead terminal
`die-bonded,
`preferably arranged at the other endofthe plurality of lead
`terminals respectively disposed along one side region.
`Accordingly,
`the predetermined lead terminal and the
`another predetermined lead terminal connectedto the reflec-
`tor are disposed such that
`the distance therebetween is
`greatest. As a result, the reflector can be supported and fixed
`more stably by the predetermined lead terminal and the
`another predetermined lead terminal.
`In the above-described case where the lead frame includes
`
`another predetermined lead terminal connected to the region
`of the lead frame to which the semiconductor light emitting
`element is die-bonded, the sealing member includes side
`regions facing each other, and the predetermined lead ter-
`minals are arranged so as to protrude from the sealing
`memberalong respective side regions facing each other, the
`predetermined lead terminal and the another predetermined
`lead terminal are preferably disposed at a position where the
`distance between the predetermined lead terminal and the
`another predetermined lead terminal is greatest.
`Accordingly, the reflector is supported and fixed more
`stably through the predetermined lead terminal and the
`another predetermined lead terminal by virtue of the prede-
`termined lead terminal and another predetermined lead
`terminal connected to the reflector such that the distance
`between these lead terminals is greatest.
`There is further provided a groove at a region of the
`sealing member wherethe reflector is located to receive the
`predetermined lead terminal. The depth of the groove is
`preferably set such that the surface of the predetermined lead
`terminal and the surface of the sealing member where the
`reflector is located is substantially on the same plane as the
`predetermined lead terminal received in the groove.
`Bysetting the top face of the predetermined lead terminal
`substantially flush with the top face of the sealing member,
`the reflector is brought into contact with the sealing member
`in addition to the predetermined lead terminal. As a result,
`the reflector can be supported andfixed further stably by the
`predetermined lead terminal and sealing member.
`Alternatively, the reflector can be formed by folding and
`bending a memberthat becomesthe reflector. This member
`is formed integrally with the predetermined lead terminal in
`an unfolded manner, corresponding to an expansion plan.
`In this case, the step of coupling the predetermined lead
`terminal with the reflector is no longer required. Since the
`reflector is formed integrally with the leading end of the
`predetermined lead terminal, the reflector can be supported
`reliably by the predetermined lead terminal.
`Such a member to constitute a reflector specifically
`includes a reflector body and another reflector body, a
`projection provided at one of the reflector body and the
`another reflector body, and a notch provided at the other of
`the reflector body and the another reflector body. In the
`reflector, the projection preferably engages with the notch.
`In the case where the reflector is provided as a separate
`piece without being formed integrally with the leading end
`of the predetermined lead terminal, the degree of freedom of
`the configuration of the reflector is increased. For example,
`in the case wherethere is another sealing memberthat seals
`another lead frame to which another semiconductor light
`emitting elementis die-bonded, the reflector can be disposed
`so as to bridge between the sealing memberand the another
`sealing member.
`Furthermore, the reflector preferably includes at least one
`of a flat portion and a curved portion as the region to reflect
`light from the standpoint of improving the degree of free-
`dom oflight reflection.
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`Specifically, a reflector can be used having a reflection
`plane whose configuration in cross section parallel to the
`optical axis is formedofa straightline, or a reflection plane
`whose configuration in cross section parallel to the optical
`axis is formed of a curve constituting a parabola, a portion
`of an ellipse, or an arc. Furthermore, a reflector can be used
`whose configuration in plane in a direction substantially
`orthogonalto the optical axis is a rectangle, a shape formed
`of two ares and a straight line connecting these arcs, a shape
`corresponding to a portion of the curve of an ellipse or a
`parabola being partially coupled, or the like.
`In order to release heatefficiently from the reflector to the
`air, preferably the entire reflector is exposed to theair.
`The foregoing and other objects, features, aspects and
`advantages of the present
`invention will become more
`apparent from the following detailed description of the
`present
`invention when taken in conjunction with the
`accompanying drawings.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a perspective view of a semiconductor light
`emitting device according to a first embodiment of the
`present invention.
`FIG. 2 is a plan view of a modification of the semicon-
`ductor light emitting device of the first embodiment.
`FIG. 3 is a plan view of a semiconductor light emitting
`device according to a second embodiment of the present
`invention.
`FIG.4 is a side view of the semiconductor light emitting
`device of FIG. 3.
`FIG. 5 is an exploded plan view of a semiconductorlight
`emitting device according to a third embodiment of the
`present invention.
`FIG. 6 is a perspective view of the semiconductor light
`emitting device of FIG. 5 of the third embodiment.
`FIG.7 is an exploded plan view of a semiconductorlight
`emitting device according to a fourth embodiment of the
`present invention.
`FIGS. 8, 9 and 10 are sectional views of the semiconduc-
`tor light emitting device of respective embodiments, repre-
`senting examples of the configuration of the cross section of
`the reflector.
`FIGS. 11, 12, 13 and 14 are sectional views of the
`semiconductor light emitting device of respective embodi-
`ments, representing examples of the configuration of the
`plane ofthe reflector.
`FIG. 15 is a sectional view of a conventional semicon-
`ductor light emitting device.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`First Embodiment
`
`Referring to FIGS. 1 and 2, a semiconductor light emit-
`ting device according to a first embodiment of the present
`invention has an opening 10 formedat a top face of a resin
`package 3. A light emitting element 2 is die-bonded to a
`region of a lead frame 1 exposed at the bottom of opening
`10. At a top face of resin package 3, a reflector 5 is attached
`to direct the light emitted by the light emitting element 2
`towards a predetermined direction. Reflector 5 is attached
`such that its entirety is exposed to the air.
`Respective lead terminals 4a and 46 of lead frame 1 are
`disposed so as to project from each of the two opposite side
`regions of resin package 3. Among the plurality of lead
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`5
`terminals 4a and 4b, a predetermined lead terminal 4a
`connected to the region where light emitting element 2 is
`die-bondedis bent upward. The leading endofthe bent lead
`terminal 4a is soldered by, for example, solder paste 6 to a
`fringe portion identified as an attach region 5aofreflector 5.
`The remaining lead terminals 44 are respectively bent down-
`wards for connection to the wiring (not shown) formedat the
`substrate. Lead terminal 40 is electrically connected to light
`emitting element 2 via leads 2a and 2d.
`The two lead terminals 4a connected to reflector 5 are
`
`disposed diagonally opposite to each other at resin package
`3 such that the distance between these two lead terminals is
`
`greatest.
`light emitting
`In the above-described semiconductor
`device, lead terminal 4a connected to the region wherelight
`emitting element 2 is die-bonded is connectedto reflector 5.
`Accordingly, the heat generated at light emitting element 2
`is reliably conductedto reflector 5 via lead terminal 4a. The
`heat conductedto reflector 5 is releasedefficiently to the air
`by reflector 5 that is entirely exposed to the air.
`light
`By the efficient dissipation of heat generated at
`emitting element 2 through reflector 5, a relatively large
`current can be conductedto light emitting element 2 to allow
`increase of the luminosity. Furthermore,
`temperature
`increase of the light emitting element
`is suppressed to
`improve the reliability of light emitting element 2. Addi-
`tionally, degradation of light emitting element 2 can be
`suppressed.
`The two lead terminals 4a connected to reflector 5 are
`
`disposed on the diagonal of resin package 3. Accordingly,
`reflector 5 is supported by lead terminals 4a disposed such
`that
`the distance therebetween is greatest. As a result,
`reflector 5 can be supported and fixed more stably by the
`lead terminals 4a.
`
`The present embodiment was described based on an
`example where lead terminal 4a and reflector 5 are con-
`nected by solder paste 6. Alternatively, appropriate conduc-
`tive paste such as silver (Ag) paste can be used. The
`conductive paste has high heat conduction by the inclusion
`of metal particles.
`The foregoing semiconductor light emitting device is
`described based on an example where respective lead ter-
`minals 4a and 48 are disposed projecting from two opposite
`side regions of resin package 3. Alternatively, the semicon-
`ductor light emitting device may have the lead terminals
`respectively disposed so as to protrude from only one of the
`side regions of the resin package.
`In this case,
`the two lead terminals 4a connected to
`reflector 5 are preferably disposed at one end and the other
`end such that the distance between these two lead terminals
`
`is greatest. Accordingly, reflector 5 can be supported and
`fixed more stably by the two lead terminals 4a.
`The numberof lead terminals connectedto the reflector is
`
`not limited to two; and three or more, or only one can be
`provided. Particularly in the case where only one lead
`terminal
`is connected to the reflector,
`the endmost
`lead
`terminal is preferably connected to the reflector. Accord-
`ingly, the lead terminal can be bent up towards the top face
`of the resin package while opening 10 (refer to FIG. 1)
`provided at the top face of resin package 3 is not covered.
`The reflector can be supported and fixed more stably while
`ensuring a connecting area between the reflector and lead
`terminal.
`
`6
`Second Embodiment
`
`A semiconductor light emitting device according to a
`second embodimentof the present invention is directed to
`fixing the reflector more stably to the resin package.
`Referring to FIGS. 3 and 4, a groove 3a is formed in
`advanceat the top face of resin package 3 such that the top
`plane of lead terminal 4a is substantially flush with the top
`face of resin package 3 with lead terminal 4a connected to
`reflector 5 (refer to FIG. 1)
`in a bending status. The
`remaining configuration of the semiconductorlight emitting
`device of the second embodimentis similar to the semicon-
`
`ductor light emitting device shown in FIG. 1. Therefore, the
`same elements have the same reference characters allotted,
`and description thereof will not be repeated.
`In the semiconductor light emitting device of the second
`embodiment, lead terminal 4a connected to reflector 5 is
`received in groove 3a provided at the top face of resin
`package 3 by being bent towards the top face of resin
`package 3. Accordingly, the top face of lead terminal 4a is
`substantially flush with the top face of resin package 3, so
`that reflector 5 is brought into contact with the top face of
`resin package 3 in addition to lead terminal 4a. As a result,
`reflector 5 is supported and fixed further stably by both the
`top faces of lead terminal 4a and resin package 3, as
`compared to the foregoing semiconductor light emitting
`device.
`In the semiconductor light emitting device of the second
`embodiment,
`lead terminal 4a in a bent status will not
`protrude above the top face of resin package 3. Therefore,
`the semiconductor light emitting device prior to attachment
`of a reflector can be handled easier.
`
`Third Embodiment
`
`A semiconductor light emitting device according to a third
`embodimentof the present invention hasa reflector formed
`integrally with the lead frame. Referring to FIG.5, a portion
`to becomereflector 5 is formed integrally with the leading
`end of lead terminal 4a. This portion to becomethereflector
`is formed in a state (shape) in which the reflector is spread
`out in an unfolded manner corresponding to an expansion
`plan,
`including four reflector bodies 55 in the present
`embodiment.
`
`A projection 55a is provided at one of adjacent reflector
`bodies 55. A notch 55d to be engaged with projection 55a is
`provided at the other of the adjacent reflector bodies 55.
`Bybending each reflector body 55 and holding projection
`55a of reflector body 55 under engagement with notch 555
`of an adjacentreflector body 55, reflector 5 is assembled. A
`semiconductor light emitting device havingreflector 5 at the
`top face of resin package 3 is obtained, as shown in FIG.6.
`The remaining elements are similar to those of the semi-
`conductor light emitting device of FIG. 1. Therefore, cor-
`responding elements have the same reference characters
`allotted, and description thereof will not be repeated.
`In the semiconductor light emitting device of the third
`embodiment, the portion to becomereflector 5 is formed
`integrally with the leading end of lead terminal da, taking a
`configuration in which reflector 5 is spread out
`in an
`unfolded manner corresponding to an expansion plan.
`Therefore,
`the step of connecting lead terminal 4a with
`reflector 5 is not longer necessary. Assembly ofthe portions
`constituting the reflector leads to a state wherereflectorplate
`5 is attachedintegrally to the leading endof lead terminal 4a.
`Asa result, reflector 5 is reliably supported andfixed to lead
`terminal 4a.
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`7
`Since reflector plate 5 and lead terminal 4a are connected
`integrally, higher heat conduction is achieved, as compared
`to the case wherethe reflector plate is attached to the lead
`terminal. Thus, heat dissipation can be effected more effi-
`ciently.
`The semiconductor light emitting device set forth above
`wasdescribed based on an example havinga flat reflection
`plane for the reflector. Alternatively, a reflector having a
`curvedreflection plane can be employed depending uponthe
`shape in which the reflector is spread out in an unfolded
`mannerandthe assembly by, for example a bending process.
`
`Fourth Embodiment
`
`A semiconductor light emitting device including a plu-
`rality of resin packages in which a light emitting elementis
`incorporated will be described here as a semiconductorlight
`emitting device of the fourth embodiment. Referring to FIG.
`7, reflector 5 is disposed so as to bridge across two resin
`packages 3. A lead terminal 4a connected to the portion
`wherea light emitting element (not shown) is die-bondedis
`connected to reflector 5, likewise the semiconductor light
`emitting device described above.
`Byproviding reflector 5 separately from the lead frame in
`the semiconductorlight emitting device set forth above, the
`degree of freedom for attaching reflector 5 becomes higher.
`Onereflector 5 can be attached with respect to two resin
`packages 3. Since lead terminal 4a coupled to the region
`where light emitting element 2 is die-bonded is connected,
`the heat generated at light emitting element 2 can be released
`efficiently by reflector 5. As a result, the heat conducted to
`reflector 5 can be released efficiently through reflector 5.
`The above embodiment was described based on an
`
`example in which one reflector 5 is provided for two resin
`packages 3. The numberof resin packages 3 is not limited
`to two. A semiconductor light-emitting device having one
`reflector arranged for three or more resin packages can be
`provided.
`The semiconductor light emitting devices of respective
`embodiments set forth above were described based on an
`
`example in which reflector 5 has a reflection plane whose
`configuration in cross section along an optical axis 11 is
`formedof a straight line, as shown in FIG.8. Additionally,
`a reflector 5 having a reflection plane whose configuration in
`cross section is formed of a curve constituting a parabola or
`a portion of an ellipse can be disposedat the resin package,
`as shown in FIG. 9. Alternatively, a reflector 5 having a
`reflection plane whose configuration in cross section is
`formed of a curve constituting an are can be disposedat the
`resin package, as shown in FIG. 10.
`The semiconductor light emitting devices of respective
`embodiments set forth above were described based on an
`
`example in which reflector 5 whose configuration in plane in
`a direction substantially orthogonal to the optical axis is a
`rectangle. Additionally, in the case where twolight emitting
`elements 2 are arranged, a reflector 5 whose configuration in
`plane in a direction substantially orthogonal to the optical
`axis is an ellipse with a major axis set along the direction
`where the two light emitting elements are arranged can be
`disposed at resin package 3, as shown in FIG. 11.
`Furthermore, a reflector 5 whose configuration in plane
`takes a shape formed of two arcs and a straight line con-
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`55
`
`60
`
`8
`necting these arcs can be disposed at resin package 3, as
`shown in FIG. 12. Alternatively, a reflector 5 whose con-
`figuration in plane takes a shape corresponding to a portion
`of the curve of an ellipse, a parabola or the like being
`coupled, can be disposed at resin package 3, as shown in
`FIG. 13.
`
`In a reflector whose configuration in plane in a direction
`substantially orthogonal to the optical axis is a rectangle, the
`four sheet-like reflection planes are preferably disposed in
`an inclined manner such that each spreads upwards, as
`shown in FIG. 14. Accordingly, light emitted from the light
`emitting element can be outputefficiently in one direction.
`Byprovidingthe reflector as a separate piece with respect
`to the lead frame, the shape of the reflector can be selected
`in accordance with the semiconductor light emitting device.
`The degree of freedom of the emission property of light
`output from the light emitting element becomes higher.
`Furthermore, with regards to a common semiconductorlight
`emitting device prior to attachment ofa reflector, various
`reflectors can be applied.
`Although the present invention has been described and
`illustrated in detail, it is clearly understood that the sameis
`by way ofillustration and example only and is not to be
`taken by wayoflimitation, the spirit and scopeofthe present
`invention being limited only by the terms of the appended
`claims.
`
`Whatis claimedis:
`
`1. A semiconductor light emitting device comprising:
`a lead frame including a plurality of lead terminals,
`a semiconductorlight emitting element die-bondedto said
`lead frame,
`a sealing membersealing said lead frame such that each
`of said plurality of lead terminals and said semicon-
`ductor light emitting element are exposed, and
`a reflector attached to said sealing memberto direct light
`emitted by said semiconductor light emitting element
`towards one direction,
`wherein a predetermined lead terminal among said plu-
`rality of lead terminals is arranged towards a side where
`said reflector is located and connectedto said reflector,
`said predetermined lead terminal being connected to a
`portion of said lead frame to which said semiconductor
`light emitting element is die-bonded,
`wherein said reflector is formed by bending a memberto
`becomesaid reflector, formed integrally with said pre-
`determined lead terminal in a state in whichthe reflec-
`tor is spread out in an unfolded mannercorresponding
`to an expansion plan.
`2. The semiconductor light emitting device according to
`claim 1, wherein said member to becomea reflector com-
`prises
`a reflector body and anotherreflector body,
`a projection provided at one of said reflector body and
`said another reflector body, and
`a notch provided at the other of said reflector body and
`said another reflector body,
`said projection being engaged with said notch at said
`reflector.
`
`Cree Ex. 1006
`
`Page 13
`
`Cree Ex. 1006
`
`Page 13
`
`